Residents of a small town in Oklahoma have filed a class-action lawsuit against 27 energy companies, charging that the firms' wastewater injection wells cause frequent earthquakes.

The lawsuit accuses the companies of polluting the environment with practices that result in man-made earthquakes. Oklahoma has been hit by thousands of earthquakes in recent years, many of which scientists have said are due to drilling teams' practice of injecting fluids deep underground to bring up natural gas and oil.

The wastewater produced by such drilling processes is pumped back into the ground via disposal wells. It is that action that plays a major role in causing earthquakes, scientists believe, because the increase in pressure underground destabilizes seismic fault lines and causes massive rock formations to shift, shaking the ground above.

The suit filed Thursday in Oklahoma's Pawnee County District Court listed Eagle Road Oil LLC, Cummings Oil Company and 25 other unnamed defendants. The plaintiffs are seeking a nonspecific amount of damages — a sum "sufficient to punish" the energy companies and enough to "deter them from such conduct in the future."

Two particularly devastating earthquakes struck Oklahoma in September and October. A 5.8 magnitude quake in Pawnee was the strongest ever recorded in the state; that jolt, along with another in nearby Cushing measuring 5.0, damaged dozens of buildings.

Oklahoma had not been known as as a site of frequent earthquakes until the energy business expanded there in recent years. Between 2009 and 2015, earthquakes in the state increased from a maximum of 187 per year to 5,838. As the frequency of tremors has increased, so has their severity.

"These waste-induced earthquakes have toppled historic towers, caused parts of houses to fall and injure people, cracked basements and shattered nerves as people fear there could be far worse," the plaintiffs wrote in their complaint.

Neither of the two companies named in the lawsuit has responded to the court filing. If the lawsuit continues, more Oklahoma residents could join the list of plaintiffs.